Stapling machine



April 13, 1939- E. KRANTZ 2,154,755

STAPLING MACHINE Filed NOV. 19, 1956 3 Sheets-Sheet l 72067351": EdwamUf a Z 3 Sheets-Sheet 2 E. KRANTZ STAPLING MACHINE Filed Nov. 19, 1956 April 18, 1939.

Am mm m In i fl r IN 6 VIII/17171 'STAPLING MACHINE Filed Nov. 19, 1936 3 Sheets-Sheet 3 6 h 15 Q g2 y A I '65 23 .l I v Patented Apr. 18, 1939 UNITED STATES STAPLING MACHINE Edward Krantz, Chicago, 111., assignor to Fastener OaIrpoI-ation, Chicago, 111., a corporation of Application November 19, 1936, Serial No. 111,030

6 Claims.

This invention has to do with stapling machines of the type in which the staples are driven into the paper or other material by means of a springactuated hammer.

5 The object of the invention is to provide an improved stapling machine of the character described which will operate efliciently in the manner intended, will give trouble-free service over along period of time, requires no periodic adjust- 10 ing, is quiet in its operation, can be opened up readily to permit the removal of any defective staples which may clog up the guideway for the driving blade, and can be manufactured at comparatively small cost.

15 While the foregoing statements are indicative in a general way of the nature of the invention, other objects and advantages will be evident upon a full understanding of the construction, arrangement and operation of the parts which 20 make up the machine.

A preferred embodiment of the inventionnamely, a desk or office type of stapling machine-is presented herein for the purpose of exemplification, but it will of course be ap- 25 preciated that the invention is capable of incorporation in other forms coming equally within the scope of the appended claims.

In the accompanying drawings:

Fig. 1 is a top view of a stapling machine con- 80 structed in accordance with the invention;

Fig. 2 is a side view of the machine; Fig. 3 is a partially sectioned side view; Fig. 4 is a horizontal section, taken on the line Fig. 5 is another horizontal section, taken on he line 5-5 of Fig. 3;

Fig. 6 is a vertical section, taken on the line H of Fig. 4;

Fig. '7 is a partially sectioned side view of the 4 follower which is attached to the draw band;

Fig. 8 is a view which corresponds to Fig. 3 but shows the parts of the machine in the positions which they assume just as a staple is about to be driven;

m. 9 is a vertical section, taken on the line H of Fig. 2;

Fig. 10 is a perspective view, showing the lower end of the staple-driving blade and the front end of the staple-supporting bar;

Fig. 11 is a top view of the finger piece on the rear end of the draw band; and

Fig. 12 is a fragmentary side view of the machine at the location of the displaceable front so guide plate, showing'the latter swung forwardly and downwardly to expose the driving blade and the guideway in which the blade moves.

Referring in more detail to the drawings, it will be observed that the machine includes a base I! and a head-ll. The base II is provided at its front end with a clinching die I 2 and at its rear end with a bracket ll of upwardly opening channel form in which the rear end of the head II is supported on a hinge pin l4. The lower part of the head I l is in the form of an arm l5, while the upper part of the head'is in the form of a casing I. The arm I! and casing l6 are connected with each other at their front ends by spaced side plates l1 and are separated from each other at their rear ends by a slot l8. 15 The head II is provided at its front end with a vertically extending guideway ll of rectangular cross section in which a plunger or corresponding cross section is slidably mounted. This plunger carries a staple-driving blade 2| which so is set back into a closely conforming cut-out por tion in the front face of the plunger and is held in position by means of a rivet 22. The blade 2| moves up and down in a small slot 23 which is located in the head directly above and clinching 26 die i2 on the base.

The arm l5, which forms the lower part of the hinged head II, is composed of two nested channel members 24 and 25. The inner member 25 is spaced from the outer member 24 at its top and at the upper portions of its sides (see Fig. 9), whereby to provide between the members a guide way 26 of inverted U-shape cross section for the reception of a large number of staples 21, which staples straddle and slide along the top of the inner member 25. The inner member 25 is closed off at its front end and is cut back, along with the overlying portion of the outer member 24 (see Fig. 10), to form the previously described slot 23 in which the staple-driving blade 2| moves. The staples 21 are advanced along the guideway 25 by a sheet metal follower 28 (see Fig. 7) which "is positioned in the guideway behind the rearmost staple. The follower 28 is provided with a button-like stud 29 which projects upwardly through a slot 30 in the top of the channel member 24 and is hooked through an aperture 3| in a finger piece 32 (see Fig. 11) attached to a draw band 33. The draw band is a strip of spring metal which is secured to a hub 34 and wound resiliently into a coil by means of the hub to apply constant tractive force to the follower. Under the action of the draw band 23 the finger piece 32 will move forwardly in the previously described slot II in the head as the staples are used up.

The staple-driving plunger 26 is projected downwardly in the guideway It by the action oi a coil spring 86. The spring 66 is positioned in the rear end of the casing l6 between the bottom of the casing and the rear end of a lever 34. The lever I6 is fulcrumed near its rear end on a pin 31 and is provided a short distance in front of the pin with a bumper block 36 for cushioning engagement with the bottom of the casing. The

lever 36 is of channel form and is provided at its front end with two rounded cars 36 which extend forwardly from the two sides of the channel into undercut grooves 40 in the sides of the plunger. When the plunger is raised in its guideway the spring 36 will be compressed, with the result that when the plunger is released it will be driven downwardly by the spring with considerable force and speed and will deliver a hammerlike blow against the staple under the blade 2|.

The plunger 26 is raised against the resistance of the spring by means of a hand lever 4i, which lever is pivctally mountedat its rear end on a pin 42 in the rear part of the casing [6. The lever 4| extends forwardly and upwardly through a narrow slot 43 in the center of the top of the casing and terminates in a round knob-like handle 44 which is located above the front end of the head ii. A roller 45, which is mounted on the under side of the lever 4|, bears against the rear end of a lever 46. The lever 46 is pivotally mounted intermediate its ends on a pin 41, and the front end of the lever extends under a hook 46 on a dog 49 carried by the plunger 20. The dog 46 is pivotally mounted in a slot I 60 in the center of the plunger (see Figs. 4, 5 and 6), on a pin 5|, and the upper hooked end of the dog is pressed at all times in the direction of the lever 46 by a small spring 52 which is seated in a recess in the plunger. The dog is provided below the pin 5! with a projection 53 which acts against one side of the slot in the plunger to limit the extent to which the dog can be tilted by the spring 52. The rear end of the lever 46 is maintained at all times in engagement with the roller 46 by a spring 54 which is positioned beneath that end of the lever. This spring also serves to maintain the operating lever 4| elevated, which is the normal position of that lever when the machine is not actually in operation.

When the plunger 20, in being raised by a downward movement of the handle 44, approaches its uppermost position, a beveled surface 55 on the top of the dog 49 will come into contact with a stud 66 in the top of the casing i6. As the plunger is elevated into its highest position this stud will cam the upper end of the dog forwardly, and as soon as the hook 48 on the dog clears the front end of the lever 46 the plunger will be released and will travel downwardly in the guideway l9 under the action of the then compressed spring 36.

The lower part of the front wall of the guideway 23 for the blade 2i consists of a removable plate 61. This plate is held in position by two thumb screws 56 which pass through apertures 69 in two side flanges 60 on the plate into threaded openings in the sides of the arm i6 (see Figs. 2 and 12). The apertures 69 are of keyhole shape and the shanks of the screws near the heads are of conical shape, whereby when the screws are loosened the plate 61 can be pulled away from the end of the arm I! a short distance without the screws having to be entirely removed and when the screws are tightened with .the plate pushed back the latter will be drawn intoexactly the right position by the centering action of the conical portions of the screws on the enlarged portions of the keyhole apertures. When the plate 61 is pushed back slots II in the ends of the flanges 60 will engage with indexing pins 62 on the arm l6, insuring proper vertical registration of the plate 61 with the upper fixed portion of the guideway ll. This construction gives easy access to the guideway 28 at the point where the staples enter the same, and insures an accurate positioning of the parts after the guideway has been cleared.

The front end of the head I I is normally main tained in a slightly raised position with respect to the base-i6 by means of a spring 66 (see Fig.

9) which is located between the head and the base in the bracket i3 at a point a little in front of the hinge connection i 4. The spring 63 acts to support a bolt 64 which extends upwardly through an aperture in the base and is provided at its upper end with a nut 66. The nut II is prevented from turning by reason of its close fit with the sides of the bracket, and the spring 68 is compressed between the nut and the bottom of the bracket. When the machine is operated the initial pressure placed on the handle 44 will move the head ll downwardly against the yielding resistance uttered by the upwardly springpressed bolt 64, forcing the head into engage- -ment with the paper or other material on the base i0. To vary the normal spacing between the head and the base it is merely necessary to turn the bolt in one direction or the other.

When it becomes necessary to insert a fresh supply of staples into the guideway 26 in the arm IS, the finger piece 32 is unhooked from the stud 29 and is pulled out and hooked over a stud 66 on the rear end of the casing i6, as shown in dotted lines in Fig. 2. After this has been done the follower 28 can be backed out of the open rear end of the guideway 26 and the new supply of staples can be inserted into the guideway without either the draw band or the finger piece being in the way.

I claim:

1. In a stapling machine, a head containing in the front portion thereof vertically movable staple driving plunger, a spring in the rear portion of the head for moving the plunger downwardly to drive a staple, a power transmitting connection in the head between the spring and the plunger, an operating lever having a handle which when depressed raises the plunger against the yielding resistance of the spring, a releasable connection between the operating lever and the plunger which includes a pivoted hook on'the plunger, and means for automatically moving the hook into a disengaged position when the plunger reaches the upper end of its movement.

2. In a stapling machine, a head containing a vertically movable staple driving plunger, a spring for moving the plunger downwardly to drive a staple, and means for transmitting the force of the spring to the plunger consisting of a driving lever which is pivoted intermediate its ends tospring to the plunger consisting of a driving lever which is pivoted intermediate its ends to the casing with its front end in engagement with the plunger and its rear end in engagement with the spring, and means for cushioning the driving movement of said lever consisting of a rubber block attached to the lever in front of the pivotal axis of the latter for engagement with the bottom of the casing.

4. In a stapling machine, a head in the form of a hollow casing, a vertically movable staple driving plunger in the front of the casing, a coil spring in the rear of the casing for moving the plunger downwardly, a driving lever pivoted intermediate its ends to the casing with its front end in engagement with the plunger and its rear end in engagement with the spring, an operating lever pivoted at its rear end to the casing and provided at its front end with a handle, a hook pivoted to the plunger, a lifting lever pivoted intermediate its ends to the casing with its front end in engagement with the hook and its rear end in engagement with the operating lever, and a stop in the casing above the hook for camming the latter out of engagement with the fnont'end of the lifting lever when the plunger reaches its uppermost position, whereby to allow the plunger to descend under the action of the spring 5. In a stapling machine, a head containing a vertical guideway, and a staple driving blade in the guideway, said guideway being characterized by a removable front wall section provided with side flanges, and screws passing through elongated keyhole apertures in the flanges into threaded openings in the sides of the head for securing the removable front wall section in operative position, said screws having enlarged shank portions which index in the enlarged ends of the keyhole apertures when the screws are tightened'with the front wall section in operative position.

6. In a stapling machine, a casing, an underlying arm which is connected to the casing at its front end and is separated from the casing at its rear end by an intervening slot, a staple driving mechanism positioned in the casing, a staple follower slidably mounted on the arm in the slot, a tensioned draw band for the follower having a finger piece detachably looped over a portion of the follower, anda hook on the rear end of the casing for holding the finger piece and draw band in an out-of-the-way position while the follower is being removed or replaced.

EDWARD mm 

